Hi SCK,
When you complete 5 years, you have 4 options
1- apply for citizenship
2- renew your GV
3- apply for GV PR
4- apply for normal PR
Option 1 can be done in parallel with any other option.
You need to have A2 language level and provide some additional documents…the process takes 1.5-2 years.
Option 2 is standard and similar to any renewal you did before. You will get a new card with 2 year duration.
Option 3 is a 5 year PR specially designed for GV holders who have completed 5 years. It requires a language A2 level, and costs 7000 Euros (approx). This allows you to be a resident for 5 years without residing in the country. There is a very nice post about this in the forum here.
Option 4 is a 5 year PR, which costs almost nothing.
It requires a language A2 level and requires you to reside in Portugal for 180 days for every year.
Due to the current situation I recommend anyone who reaches 5 years apply for citizenship immediately and in parallel apply for GV PR.
Regards,
Bisho